Alpena weekly argus. [volume] (Alpena, Mich.) 1871-1893, 1887-11-16
FACTS ABOUT The SEA.
Some Interesting Considerations Present,
by the Deptha Of tho Ocean.

Some Interesting Considerattons Presented
by the Depths OF the Ocean.
The sea Is the reservoir into which
run all the rivers of the world. 1t is
the cistern which finally catches all the
rain that falls, not only upon its own
surface, but upon the surface of the
land and upon the roofs Of our homes.
All this water is removed again by
evaporation as fast as it is supplied
IL is estimated that every year layer
of the entire sea, fourteen feet thick,
is taken up into the clouds. This
vapor is fresh. and IL all the water
could be removed in the same way and
none OF it returned, 1t is calculated
that there would be left layer of pure
salt two hundred and thirty feet thick
on the bed Of the Atlantic.
This is upon the supposition that
three feet depth of water contains one
inch depth Of SALT and that the average
depth of the ocean is three miles. At
depth of about three thousand FIVE
hundred feet the temperature is uni
form. varying but trife between tho
poles and the equator. The colder
water is below. 1t is reported that in
many deep bays on the coast Of Norway,
the water often begins to freeze at the
bottom before 1t does at the surface.
At this depth waves are not felt. Waves
do not travel-that Is. the water does
not move forward, although it seems to
do SO; it stays in the same place. The
rising and falling moves on.
We measure waves by their height,
and by the distance from crest to crest.
In deep water this latter distance Is
about fifteen times the height of the
wave. In shallow water tho proportion
is less, and this makes choppy sea.
The force Of waves is in proportion to
their height 1t is said that the sea
strikes on Bell Rock with tho force Of
seventeen tons for each square yard.
The pressure of the water increases as
we 60 down. At the depth Of a mile
this pressure is reckoned at more than
a ton to the square inch, that is, more
than hundred and thirty-three times
the pressure Of the atmosphere.
To get correct sounding in deep
water is difficult. A shot weighing
thirty pounds carries down the line.
Through this sinker hole is bored.
and through the hole is passed rod Of
iron which moves easily back and forth.
In the end OF the bar cup is dug out,
and the inside is coated with lard. The
bar is made fast to the line and sling
holds the shot on. When the bar which
extends below the shot, touches the
bottom, the sling unhooks and the shot
slides of. The cup in the end Of the
bar holds some of the sand, or whatever
may be on the bottom, and a cover
shuts over the cup to keep the water
from washing the sand out. In this
way we learn the character of the deep
sea bottom. 1t will be seen at once that
we can know the depressions Of the
bottom ofthe ocean more easily and
more accurately than we can learn the
elevation of the land. AS consequence
we have better typographical map Of
much of that surface than we have Of
the continents.
The depth of the sea presents some
interesting considerations. If the At
lantic were lowered six thousand five
hundred and sixty-four feet, it would
be reduced to half its present width. II
it were lowered little more than three
miles, there would be dry land all the
way between Newfoundland and Ire
land. If the Mediterranean were
lowered six hundred and sixty feet,
Africa would be joined to Italy, and
three separate seas would remain
Youths Go,nnnuion